Professional and amateur athletes have an annual calendar with many competitions, so they can be susceptible to injury. Muscle and joint injuries can occur due to external and internal factors. In general, overuse or lack training load, neglecting to control training volume and intensity, low levels of strength, poor joint mobility and flexibility, low energy availability, insufficient recovery can result in muscle and joint injuries.
The type, time away from training, frequency and severity depend on various factors, with muscle injuries representing the most frequent cause of physical incapacity, comprising approximately 70 per cent of all injuries, followed by ligament and joint injuries. In addition, 72 per cent of injuries occur during competitions and 22 per cent during training.
Nutrition plays a fundamental role in the rehabilitation process of athletes. Depending on the injury, athletes can spend weeks or months in the rehabilitation process, which can negatively affect muscle mass, as well as changes at cellular level, in the immune system and in bone mass. So, let's understand the stages of injury.
Stages of injury: Immediately after the injury, the inflammatory response begins. It's the first defence mechanism for repairing the affected tissue.
Phase 1: Immobilisation and atrophy: In this phase, the loss of muscle mass due to disuse begins. Loss of muscle mass can occur within a few days of the injury. This is due to the phenomenon we call negative muscle protein balance, when the rate of synthesis is lower than the rate of muscle protein degradation. Mitochondrial oxidative function is also affected by disuse.
Phase 2: Rehabilitation and Hypertrophy: In this phase the exercise protocols for the affected limb begin, as well as optimising the performance gains of the unaffected limbs.
Energy Demand: Depending on the severity of the injury, calorific intake may be similar to that before the injury. This is because the basal metabolic rate can increase by more than 20 per cent. Severe calorie restriction during the period of inactivity or rehabilitation is not a good strategy, because if protein and other macronutrient intake is not optimal, it can negatively affect muscle mass. Between the period of injury and rehabilitation, a weight gain of between 2 and 4kg can be considered acceptable.
The importance of protein and supplementation
Protein: The macronutrient most often associated with nutritional interventions aimed at sports injuries. Proteins act as building blocks for muscle, tendons and other soft tissues, and are essential in the production of enzymes, hormones and neurotransmitters necessary for various bodily functions.
During the rehabilitation period, a protein intake of 2.0g/kg/day or more is recommended. In addition to the absolute amount of protein of high biological value per day, the frequency of consumption should also be taken into account. We recommend 4 to 5 meals/day with an amount of protein between 0.30 and 0.40g/kg per meal.
CREATINE: The use of creatine is essential during the rehabilitation process. A dosage of 5g/day can help maintain muscle mass during treatment and optimise hypertrophy gains during the return to play period.
VITAMIN D: The importance of vitamin D is not restricted solely to the prevention of bone injuries. Vitamin D supplementation helps regulate the expression of genes in type 2 muscle fiber and reduces biomarkers of muscle damage and pro-inflammatory cytokines. Prior testing of serum 25-hydroxyvitamin D concentration is necessary before supplementing.
COLLAGEN TYPE 2: The supplementation of collagen peptides seems to be beneficial for its synthesis in the body and can prevent injuries, help with joint, ligament and tendon repair and relieve pain. There is still much debate in the literature about their real effects.
Omega-3: The use of omega-3 is often associated with the treatment of sports injuries due to its anti-inflammatory, immunomodulatory properties and anti-catabolic effects on muscles. Supplementation should be adjusted to the stage of treatment.
As well as macronutrients, the intake of micronutrients is extremely important. Poor intake of vitamins and minerals, especially calcium, zinc, magnesium, iron and vitamin C, can lead to poor performance and increase the risk of muscle and joint injuries. Vitamin C supplementation during the injury phase can be even more useful because of its role in healing. Vitamin C deficiency is linked to a decrease in collagen synthesis.
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